Rough or irregular terrain poses difficulty for vehicles attempting to traverse the terrain. This is particularly true for robotic vehicles, and indeed robotic vehicles may frequently be called upon to traverse rough or irregular terrain. Various attempts have been made to alleviate these difficulties, including spring/damper and active suspensions, hovercraft, and reciprocating leg mechanisms. However, these solutions suffer from a number of disadvantages. They variously tend be large and energy inefficient, are expensive, generate noise and suffer limitations in speed, effectiveness and load bearing capabilities.
Circular wheels are attached at their center to a hub or axle attached to the frame of a vehicle through a suspension assembly. As the surface of the wheel contacts the surface over which the vehicle is traveling, the entire wheel rises or falls with the profile of the terrain surface. To prevent such non-rotational motion of the wheel from being transferred to the frame of the vehicle, the suspension assembly employs springs, shock absorbers or struts to absorb some of the force applied through the non-rotational movement of the wheel. These suspension systems are reactionary and adjust only after the wheel changed its position relative to the vehicle frame. The suspension does not absorb all of the force of the wheel's motion and some of the energy applied by the force of the upward or downward motion of the wheel is transferred to the vehicle and its occupants.
A wheel system that is proactive and adjustable to provide a smooth ride and energy savings to address these disadvantages would be beneficial.